Study Monster Cultivation System

Chapter 158 - 157 Perfect Answer

Afterward, it took Tang Zhifei a long time to calm his emotions, wasting most of the class before finally starting the Chinese lesson.

As for the matter of class division, although it was still somewhat troublesome, that was a problem for next June or July.

At the moment, there were more pressing matters at hand.

That was the problem copied by Zhang Xiaoke.

"Three copies, one for each person, I’ll take the original," Zhang Xiaoke handed out his copies to Li Zheng and Jiang Qinghua, then bit open his pen cap with a determined air, quite in the early style of Li Zheng, "I really wonder how tricky Jingjing’s questions are."

"Right," Jiang Qinghua said coldly as he pulled out his pen, "It’s just for learning, not for rewards, we’re taking this approach, right?"

Hearing this, Li Zheng felt for the first time that Jiang Qinghua was indeed a talent worth shaping.

After being around for so long, he was finally getting on the right track, not bad at all.

Since it was a competition, Li Zheng did not cheat by speeding up but looked down at the questions as usual.

Not to mention, although he had recently tackled a massive volume of chemistry questions,

seeing physics questions felt somehow more familiar.

It was like a man who had traveled through the world’s dust, yet in the end, still loved his hometown cuisine the most.

Li Zheng stopped thinking further and began to analyze the question—

[In August 2011, China’s spacecraft "Chang’e-2," after completing its lunar mission, flew for the first time from lunar orbit to the Sun-Earth Lagrange Point.]

[At that point, "Chang’e-2" and the Earth revolved around the Sun in a synchronous circular motion.]

[The masses of the Sun and Earth are known as MS and ME, and the distance between the Sun and Earth is R.]

[The equation that the distance x from the Earth to this Lagrange Point satisfies is_______.]

[From this, x is approximately ________. (Given that when ?<<1, (1+?)^n ? 1+n?)]

Li Zheng’s first reaction after reading the question was,

it must be a physics competition question.

But not so difficult.

Completely different from the first time he encountered Chem Competition questions.

Back then, looking at those terrifying compounds, he was completely baffled and just had to buckle down, grateful for any points he could scrape together.

Because Chem Competitions involved a large amount of undergraduate-level chemistry knowledge, whether one had studied Chem Competitions made a world of difference, often not even understanding the questions.

But this physics competition question, Li Zheng could understand and had ideas right away, just unsure if he could solve it.

Lin Yujing had secretly studied for so long, and they had all been holding back on meeting for a week.

Was the physics question she presented as a greeting this simple?

Could someone like me, who had never looked at a physics competition question, even try?

Or was I too arrogant?

Maybe... it’s very difficult?

Li Zheng wasn’t sure, so he just started working on it.

The only slight difficulty in analyzing this question was the "Lagrange Point."

Li Zheng, who was steeped in science fiction, naturally understood this concept, but dwelling on it would only complicate the question.

In reality, to solve this question, there was no need to know what exactly a "Lagrange Point" was. Only paying attention to the key information provided in the question was necessary—

1. This point is on the Sun-Earth line.

2. At this point, the spacecraft and Earth revolve around the Sun in synchronous circular motion.

To a physics enthusiast, these words could instantly be transformed into geometric diagrams and mathematical equations.

Since the spacecraft is on the Sun-Earth line, this means it is affected by the gravitation of both the Earth and Sun, which are in the same direction; just add the two gravitational forces together to get the centripetal force needed for the spacecraft’s circular motion.

Since it revolves synchronously with the Earth around the Sun, this implies that the angular velocity ? is the same.

Furthermore, the relationship between angular velocity, radius, and centripetal force in circular motion is F=MR?^2.

Next, it was just a matter of laying out these equations and solving them, middle school mathematics.

Within five minutes, the answer to the first question was found.

The equation that the distance x from the Earth to this point satisfies is—

MS/(R+X)^2 + ME/X^2 = MS(R+X)/R^3

This result was somewhat complex, but the approach and calculation were indeed very straightforward.

Looking at the second question,

From this, x is approximately_____.

This... isn’t it just solving the equation above...?

Isn’t this a mathematics question now???

Looking at the equation above, it was clearly too complex; with the mathematics knowledge currently available, it was impossible to solve it directly.

The cause lay in the first part of the equation, the denominator (R+X)^2, which directly plunged the equation into the abyss.

But Li Zheng didn’t panic.

Because there was something glaring in the question prompt, almost as if it was shouting, "If you don’t know, look at me! If you don’t know, look at me!"

That was the hint in the bracket at the end.

(Given that when ?<<1, (1+?)^n ? 1+n?)

Along with the final question, which was about x?.

This was quite evident.

It was necessary to use this formula to simplify (R+X)^2.

After clarifying his thoughts, the first step was to transform (R+X)^2 into (1+?)^n.

This then became (1+X/R)^2R^2.

Subsequently, he substituted it into the formula above…

Finally, he connected it with the equation from the first question…

x?{(ME/3MS)^1/3}R

Looking at this comfortable and beautiful answer, Li Zheng took a deep breath, and his spirits lifted.

Refreshing!

Still, solving physics problems is refreshing.

There was still half a math problem left to spice things up.

Delightful!

Even though he had solved so many dreadful chemistry problems, the exhilaration they brought still didn’t compare to that of this moderately difficult physics math problem.

However, this level of difficulty...

Lin Yujing, was she really testing someone?

If she wanted to stump me, she should at least bring on some more challenging problems...

Could it be... she had some other purpose?

Was there something hidden in this problem?

Li Zheng couldn’t help but look at the problem statement again

Lagrange Point, Chang’e-2 spacecraft, synchronous orbit.

These terms, as well as the entire orbiting process, were filled with the beauty of physics.

Just like Lin Yujing’s composition titled "Her Journey."

That composition did not contain a single formula.

Instead, it described the entire physics process in a purely sentimental and graceful manner.

Upon reflection...

The solution for X was not the endpoint.

The entire process of solving the problem was to transform those beautiful words into the formula above.

Now that the result was ready, perhaps it was time to translate the numerical result back into sentimental text.

From this perspective, the ultimate question was no longer what x?.

But rather, how far must Chang’e-2 travel to dance eternally around Earth with the Sun?

Li Zheng’s eyes narrowed.

His heart thumped excitedly.

NO.

No.

No..

This was not a physics problem.

It was a problem with metaphorical implications.

I, Li Zheng, belong to the earth, equivalent to Earth.

You, Lin Yujing, are a woman, equivalent to Chang’e.

The Sun, the eternal center, represents original intentions and beliefs, equivalent to physics.

Converting that.

You, Lin Yujing, want to stay with me, Li Zheng, and enter the embrace of physics.

How far would that be?

Thinking this, Li Zheng’s face showed joy.

Ha!

I understand now.

Brilliant!

It’s just like Lin Yujing, I knew you wouldn’t set such a simple question.

You are hinting that you want to join me at Ji University Physics College, right?

If I interpreted your hint correctly, then I should fill in that answer, right?

Interesting, such a question is interesting.

Without a moment’s hesitation, Li Zheng calculated.

He then added an equal sign above the solution for X, and filled in the real answer—

[564]

564 days until the college entrance exam!